Cantilever support structure including a stationary shaft,a hollow roll shell,and a fluid pressure chamber therebetween

ABSTRACT

Fluid pressure balanced cantilever support structure, particularly adapted for paper making machinery, such as doctor backs, headbox bottom aprons and the like. The support is in the form of a stationary shaft fixed at its ends having a roll shell rotatably mounted on the shaft. The shaft and roll shell have cooperating radial vanes sealed to the respective shaft and shell and forming a fluid pressure chamber in the space therebetween. Fluid under a uniform pressure is maintained between the vanes to resist beam deflection and beam rotation.

United States Patent 1191 Brezinski 1451 Jul 31,1973

[ CANTILEVER SUPPORT STRUCTURE INCLUDING A STATIONARY SHAFT, A HOLLOW ROLL SHELL, AND A FLUID PRESSURE CHAMBER TI-IEREBETWEEN 162/274, 204, 361, 281, 336, 347; l5/256.5l, 256.5; 52/291; 118/126; 100/162 B, 174

[56] References Cited UNITED STATES PATENTS 3,327,341 6/1967 Kuehn 151256.51

l/PWARD Tl/RUST Dennis et al 162/336 X Crist 162/2 81 X Primary ExaminerS. Leon Bashore Assistant Examiner-Richard H. Tushin Attorney-Hill, Sherman, Meroni, Gross & Simpson [5 7 ABSTRACT Fluid pressure balanced cantilever support structure, particularly adapted for paper making machinery, such as doctor backs, headbox bottom aprons and the like. The support is in the form of a stationary shaft fixed at its ends having a roll shell rotatably mounted on the shaft. The shaft and roll shell have cooperating radial vanes sealed to the respective shaft and shell and forming a fluid pressure chamber in the space therebetween. Fluid under a uniform pressure is maintained between the vanes to resist beam deflection and beam rotation.

12 Claims, 3 Drawing Figures FIELD OF THE INVENTION Fluid pressure balanced cantilever support for paper making machine appurtenances such as, doctor blades, doctor backs, headbox bottom aprons and the like.

BACKGROUND, SUMMARY AND OBJECTS OF THE INVENTION In the design of paper making machinery, due to the extreme width of the machines which may be 120 inches wide and wider, many problems come up in making a full width cantilever structure supporting a plate and the like free from deflection and torque deformation. Doctor blades, doctor backs, the botton aprons of headboxes and other paper making machine appurtenances extend for the full width of the paper making machine and must be supported with their tips extending in a straight line free from beam and torque deflection.

In the present invention, this is attained by the use of a roll shell extending for at least the width of the paper making machine and supported on a stationary shaft, fixedly supported at its opposite ends. The roll shell and stationary shaft are provided with cooperating radial vanes dividing the interior of the shell into a pressure chamber extending along the portion of the roll shell subject to the deflection. Fluid under uniform pressure is then maintained in the space between the vanes to exert an upward thrust on the roll shell and a torque action thereon to hold the roll shell from vertical deflection and to counteract the torque on the roll shell by the loads on the cantilever supported member supported thereon. The cantilever supported member may be in the form of a doctor blade forming a plate extending tangentially of the periphery of the roll shell, and maintained free from deflection at its support point as well as its overhaing tip. The roll shell thus resists beam deflection and torque and the pressure of fluid in the shell may compensate for both the translational and rotational forces arising because of increased loading of the plate at its end.

An advantage of the present invention is to provide a simplified form of anti-deflection cantilever support in which the cantilever loads may be counteracted by the application of force in vertical and rotatable directions along the cantilever support. I

Another advantage of the cantilever support of the present invention over a simple beam-type antideflection device is that the support makes it unnecessary to put the resistant load at the resultant force position where it is ordinarilyplaced, when it is desired to minimize torque deflections.

A further advantage and object of the invention is to provide a fluid pressure balanced cantilever support particularly adapted for doctor backs, doctor blades, slice bodies and the like, so constructed and arranged that both translational and rotational forces arising because of increased loading are compensated for by fluid under pressure, which may be increased as the loading is increased.

Other objects, features and advantages of the invention will be readily apparent from the following description of a certain preferred embodiment thereof, taken in conjunction with the accompanying drawings,

although variations and modifications may be effected without departing from the spirit and scope of the novel concepts of the disclosure.

DESCRIPTION OF THE DRAWINGS FIG. 1 is a diagrammatic side view of a cantilever support constructed in accordance with the principles of the present invention.

FIG. 2 is a diagrammatic perspective view of the cantilever support shown in FIG. 1, with one end closure for the support removed and showing the structure supported in cantilever relation with respect thereto in the form of a plate, shown as being a doctor blade; and

FIG. 3 is a diagrammatic end view of the support shown in FIGS. 1 and 2 and illustrating an application of the support, to support a doctor blade of a paper making machine.

DESCRIPTION OF PREFERRED EMBODIMENT OF THE INVENTION In the illustrative form of the invention shown in the drawings, an anti-deflection support structure 10 is shown, which for illustrative purposes, is shown as being in the form of a roll shell 11 but which may be of various other forms. The roll shell 11 may extend for the width of a paper making machine and form a cantilever support for a roce member 12, supporting the force member free from beam and torque deformation at its end. The force member 12 is shown as being in the form of a doctor blade, but may be a doctor back having a doctor blade extending therefrom, bottom apron of a headbox or other device, which if it is to properly perform its functions must be supported to extend in a straight line along its outer end free from beam and torque deflection.

The roll shell 11 is mounted on a stationary beam 13, which is illustratively shown as being in the form of a center shaft. The center shaft 13 is shown as fixedly supported at its opposite ends on support brackets 15 in a suitable manner, which support brackets may be mounted on the foundation for a paper making machine or other support structure.

The roll shell 11 is journalled on the center shaft 13 at its opposite ends on suitable bearings (not shown) and the opposite ends of said roll shell are closed and sealed to said shaft roll shell and shaft to retain fluid under pressure in a fluid pressure chamber 16, within said roll shell and extending along the top of said roll shell along the point of connection of the force member 12 thereto.

The fluid pressure chamber 16 is formed by a radial vane 17 extending radially inwardly of an inner wall 18 of said roll shell to the center shaft 13 and suitably sealed thereto and sealed to the end closure for said roll shell (not shown) at its opposite ends. the opposite wall of the chamber 16 from the vane 17 is in the form of a radial vane 19 extending from the center shaft 13 to the wall 18 and suitably sealed thereto and sealed to the end closures for said roll shell (not shown) at its opposite ends in a suitable manner.

Fluid under pressure admitted to the pressure chamber 16 between the vanes 17 and 19, will thus exert an upward thrust on the roll shell throughout the length of the roll shell along line A-A and a torque on the roll shell, tending to rotate the roll shell in the direction of a torque arrow shown in FIG. 2, against a uniform load 3 over the entire force member along line B-B or at either end of said force member along line BB.

As shown in FIG. 1, the interior of the roll shell is connected with a suitable source of pressure through a pressure line 21 extending through the end closure member, therefor (not shown) and having a pressure regulator 23 therein maintaining the fluid under pressure in a pressure chamber 16 uniform throughout the length of said chamber. The pressure regulator 23 may be a constant pressure outlet valve of a conventional form, which can be regulated to vary the pressure in said pressure chamber 16, as required. The pressure regulator may be regulated to increase or decrease the uniform pressure within the pressure chamber throughout the length of the roll shell, as the loads on the end of the load member increase or decrease.

The volume of the fluid pressure chambers 16 may be varied by angularly adjusting the vane 19 relative to the vane 17, by varying the position of the center shaft in the support 15, to provide the required area of the internal wall 18, subject to deflection correcting pressures, to counteract the beam deflecting or bending forces, and balance the torque forces on the roll shell. This adjustment may be attained by loosening the support brackets and positioning the vane 19 in the required position to balance the torque and antideflecting forces, or in any other suitable manner.

in FIG. 3, l have shown the load member 12 as a doctor blade with the roll shell 11, forming in effect a doctor back. As shown herein, a web 25 passes under a back-up roll 26 and over a coating applicator roll 27 rotating in a coating solution contained in a coating pan 29 to coat the web 25 in a manner well-known to those skilled in the art, so not herein shown or described further. The doctor blade 12 is positioned on the outgoing side of the applicator roll 27 to doctor excess coating solution from the web. The cantilever support may thus load the overhanging end of the load member or doctor blade 12 uniformly throughout the length of said load member, and also by exerting an upward thrust on the interior of the roll shell along line A-A holds the roll shell from beam deflection, and thus provides a uniform upward anti-deflection thrust over the entire length of the roll shell,

While I have illustratively shown the force member as being in the form ofa doctor blade, extending generally tangentially from the roll shell, it is of course understood that the force member may be any member having a cantilever supported end in which it is neces-' sary to support the member free from deflection along the entire length thereof. The member may thus be a doctor back as well as a doctor blade, a bottom apron ofa headbox, or any other member which is maintained without beam deflection at its support point as well as the overhanging end thereof, and that the support of the present invention has many advantages and applications in the design of slice bodies, doctor blades, doctor backs and many other structures, and particularly those structures used in the paper making art.

in summary, the structure shown in the drawings provides the elongate load member 11 which has the fluid pressure chamber 16 for transferring forces from the load member to the beam member 13. The load member has a first pressure support surface which may be termed a first pressure reactive surface and is the short circumferential segment of the inner surface 18 which is exposed to the fluid pressure chamber 16. The load member also has a second fluid pressure support surface which may be termed a second pressure reactive surface and which is the area of the vane 17 exposed to the pressure chamber 16. The beam member 13 has first and second pressure reaction surfaces which are opposed to the first and second pressure reactive surfaces of the load member or roll shell 1 l. The operating position of the roll shell 11 will be determined by its extrinsic factors. When this is determined, a fluid pressure within the chamber 16 is chosen which will exert a force on the vane 17 to counteract the torsional forces on the roll shell 11. The beam 13 is then rotated to a position to expose an inner surface area of the roll shell to the chamber 16 sufficient to provide a upward thrust from the liquid in the chamber which will support the roll shell 11 in a straight line. This is attained by loosening the support brackets 15, rotating the beam 13 and then tightening the support brackets to hold said beam in a stationary position. This will obtain optimum support for the roll shell in both a torsional direction and a vertical direction with the support forces being applied uniformly along the entire length of the roll shell inasmuch as the pressure within the chamber 16 will be uniform along the entire length of the shell. As will be appreciated, in some circumstances, it may be desirable to have the roll shell bow downwardly slightly or to bow upwardly and this can readily be accomplished by rotation of the beam 13 to decrease or increase the inner surface area exposed to the chamber 16. Thus, in effect, the radio between the surface of the vane 17 and the inner surface of the shell is changed to control the ratio between torsional and vertical forces exerted by the fluid pressure. Variations in mechanical components will be readily apparent to those skilled in the art and suitable seals and suitable adjusting means for the shaft are readily available in various forms to provide mechanical expedients.

I claim as my invention: 1. In combination, a stationary beam member, an elongated hollow load member extending along said beam member and subjected to a torsional load and to a bending load and having an internal wall spaced from said beam member, means defining a fluid pressure chamber between the beam member and the load member and directly opposing the load and transferring forces from the load member to the beam member, said means defining a fluid pressure chamber including first and second fluid pressure support surfaces on said load member exposed to the fluid in the chamber, with the first surface positioned to support the load member against bending forces and the second surface positioned to support the load member against torsional forces, and said means defining a fluid pressure chamber also including fluid pressure reaction surfaces on said beam member opposed to said first and second fluid support surfaces. 2. The construction of claim 1, wherein support brackets support and hold said load member from rotation and accommodate angular adjustment thereof to vary the ratio of the areas of said first and second surfaces relative to each other by angular adjustment of said beam member relative to said load member so that with a predetermined fluid pressure, the ratio between the forces on said first and second surfaces is variable.

3. In combination,

a stationary elongate beam member supported at its ends,

an elongate coextensive roll shell extending about said beam,

means defining a fluid pressure chamber between said beam member and said roll shell transmitting forces from the roll shell to the beam including a first radially extending reaction surface on the beam subjected to pressure in the chamber for the transmission of torsional forces,

a second circumferentially extending reaction surface on the beam,

a first radially extending fluid pressure support surface on the roll shell,

a second circumferentially extending fluid pressure support surface on the roll shell for transmitting forces from the shell to the chamber,

said first and second reaction surfaces on said beam member opposing said first and second surfaces on said beam and roll shell, the area of said second surfaces being variable by varying the position of said reaction surfaces relative to said support surfaces to adjust the ratio of bending to rotational forces transmitted to the roll shell, from the fluid in the chamber.

4. A structure in accordance with claim 3,

wherein the first fluid pressure support surface on the roll shell surface includes a radial vane on the internal surface of the roll shell extending toward the beam and the second fluid pressure support surface on the roll shell surface includes a portion of the inner circumferential surface of the roll shell,

wherein the first reaction surface on the beam includes a radial vane extending from said beam toward said roll shell, and the second reaction surface on the beam includes a portion of the outer surface of said beam between said vanes, said fluid pressure chamber being defined between said vanes and a portion of the outer surface of the beam and the interior surface of said roll shell, said beam being circumferentially adjustable to vary the area of said second surface and the volume of said fluid pressure chamber.

5. [n a fluid pressure balanced cantilever support structure,

a stationary support beam,

a roll shell mounted on said beam and having an internal cylindrical wall spaced radially from the periphery of said beam,

a cantilever force member mounted on and extending from said roll shell,

a pair of cooperating force transferring members on said internal cylindrical wall of said roll shell and on said support beam forming a fluid pressure chamber in the space between said force transmitting members,

means admitting fluid under pressure in said fluid pressure chamber at pressures sufficient to resist beam deflection of said roll shell and attain a uniform torque load along the outer end of said force member.

6. The fluid pressure balanced cantilever support structure of claim 5,

wherein the means admitting fluid under pressure in said fluid pressure chamber includes a pressure line connected between a means for supplying fluid under pressure and the fluid pressure chamber, and a pressure regulator in said pressure line, and

wherein the space between said force transferring members is adjustable, to balance the torque and beam deflecting forces.

7. The fluid pressure balanced support structure of claim 5,

wherein the beam comprises a center shaft, and

wherein the force transferring members comprise a radial vane extending from said internal cylindrical wall to said center shaft and sealed thereto, and a cooperating radial vane extending from said center shaft to said internal cylindrical wall and sealed thereto.

8. The fluid pressure balanced cantilever support structure of claim 7,

wherein the cantilever force member comprises a plate secured to said roll shell along a line midway between said radial vanes and extending generally tangentially of the periphery of said roll shell.

9. In a coating apparatus, in combination,

a uniform deflection, uniform torque cantilever support extending for the width of the machine and including,

a stationary center shaft,

means mounting said center shaft on the paper making machine at its opposite ends,

a roll shell mounted on said center shaft concentric therewith and extending therealong and mounted for rotational movement relative thereto,

said roll shell having an internal cylindrical wall spaced radially of the periphery of said center shaft, and extending for substantially the length thereof,

a cantilever force member mounted on said roll shell and extending therefrom,

a radial vane extending from said internal cylindrical wall to said center shaft and sealed thereto,

a cooperating radial vane extending from said center shaft to said internal cylindrical wall and sealed thereto,

said radial vanes defining a fluid pressure chamber in the space therebetween,

means admitting fluid under pressure to said fluid pressure chamber and maintaining a uniform pressure in said fluid pressure chamber sufficient to resist beam deflection of said roll shell, and the rotational forces on the end of said force member, and

means for supplying fluid under pressure to said fluid admitting means.

10. The coating apparatus of claim 9, wherein the force member is a doctor blade.

11. The coating apparatus of claim 10,

wherein the means admitting fluid under pressure and maintaining a uniform pressure in said pressure chamber comprises a pressure line and a pressure regulator in said pressure line.

12. The coating apparatus of claim 9,

wherein the force member is a doctor blade.

l 0' t: t I? 

1. In combination, a stationary beam member, an elongated hollow load member extending along said beam member and subjected to a torsional load and to a bending load and having an internal wall spaced from said beam member, means defining a fluid pressure chamber between the beam member and the load member and directly opposing the load and transferring forces from the load member to the beam member, said means defining a fluid pressure chamber including first and second fluid pressure support surfaces on said load member exposed to the fluid in the chamber, with the first surface positioned to support the load member against bending forces and the second surface positioned to support the load member against torsional forces, and said means defining a fluid pressure chamber also including fluid pressure reaction surfaces on said beam member opposed to said first and second fluid support surfaces.
 2. The construction of claim 1, wherein support brackets support and hold said load member from rotation and accommodate angular adjustment thereof to vary the ratio of the areas of said first and second surfaces relative to each other by angular adjustment of said beam member relative to said load member so that with a predetermined fluid pressure, the ratio between the forces on said first and second surfaces is variable.
 3. In combination, a stationary elongate beam member supported at its ends, an elongate coextensive roll shell extending about said beam, means defining a fluid pressure chamber between said beam member and said roll shell transmitting forces from the roll shell to the beam including a first radially extending reaction surface on the beam subjected to pressure in the chamber for the transmission of torsional forces, a second circumferentially extending reaction surface on the beam, a first radially extending fluid pressure support surface on the roll shell, a second circumferentially extending fluid pressure support surface on the roll shell for transmitting forces from the shell to the chamber, said first and second reaction surfaces on said beam member opposing said first and second surfaces on said beam and roll shell, the area of said second surfaces being variable by varying the position of said reaction surfaces relative to said support surfaces to adjust the ratio of bending to rotational forces transmitted to the roll shell, from the fluid in the chamber.
 4. A structure in accordance with claim 3, wherein the first fluid pressure support surface on the roll shell surface includes a radial vane on the internal surface of the roll shell extending toward the beam and the second fluid pressure support surface on the roll shell surface includes a portion of the inner circumferential surface of the roll shell, whErein the first reaction surface on the beam includes a radial vane extending from said beam toward said roll shell, and the second reaction surface on the beam includes a portion of the outer surface of said beam between said vanes, said fluid pressure chamber being defined between said vanes and a portion of the outer surface of the beam and the interior surface of said roll shell, said beam being circumferentially adjustable to vary the area of said second surface and the volume of said fluid pressure chamber.
 5. In a fluid pressure balanced cantilever support structure, a stationary support beam, a roll shell mounted on said beam and having an internal cylindrical wall spaced radially from the periphery of said beam, a cantilever force member mounted on and extending from said roll shell, a pair of cooperating force transferring members on said internal cylindrical wall of said roll shell and on said support beam forming a fluid pressure chamber in the space between said force transmitting members, means admitting fluid under pressure in said fluid pressure chamber at pressures sufficient to resist beam deflection of said roll shell and attain a uniform torque load along the outer end of said force member.
 6. The fluid pressure balanced cantilever support structure of claim 5, wherein the means admitting fluid under pressure in said fluid pressure chamber includes a pressure line connected between a means for supplying fluid under pressure and the fluid pressure chamber, and a pressure regulator in said pressure line, and wherein the space between said force transferring members is adjustable, to balance the torque and beam deflecting forces.
 7. The fluid pressure balanced support structure of claim 5, wherein the beam comprises a center shaft, and wherein the force transferring members comprise a radial vane extending from said internal cylindrical wall to said center shaft and sealed thereto, and a cooperating radial vane extending from said center shaft to said internal cylindrical wall and sealed thereto.
 8. The fluid pressure balanced cantilever support structure of claim 7, wherein the cantilever force member comprises a plate secured to said roll shell along a line midway between said radial vanes and extending generally tangentially of the periphery of said roll shell.
 9. In a coating apparatus, in combination, a uniform deflection, uniform torque cantilever support extending for the width of the machine and including, a stationary center shaft, means mounting said center shaft on the paper making machine at its opposite ends, a roll shell mounted on said center shaft concentric therewith and extending therealong and mounted for rotational movement relative thereto, said roll shell having an internal cylindrical wall spaced radially of the periphery of said center shaft, and extending for substantially the length thereof, a cantilever force member mounted on said roll shell and extending therefrom, a radial vane extending from said internal cylindrical wall to said center shaft and sealed thereto, a cooperating radial vane extending from said center shaft to said internal cylindrical wall and sealed thereto, said radial vanes defining a fluid pressure chamber in the space therebetween, means admitting fluid under pressure to said fluid pressure chamber and maintaining a uniform pressure in said fluid pressure chamber sufficient to resist beam deflection of said roll shell, and the rotational forces on the end of said force member, and means for supplying fluid under pressure to said fluid admitting means.
 10. The coating apparatus of claim 9, wherein the force member is a doctor blade.
 11. The coating apparatus of claim 10, wherein the means admitting fluid under pressure and maintaining a uniform pressure in said pressure chamber comprises a pressure line and a pressure regulator in said pressure line.
 12. The coating apparatus of claim 9, wherein the force member is a doctor blade. 